Long term followup of school based smoking prevention programs which appear successful is essential. Short term effects may fade over time and it is even possible that programs which appear ineffective initially may prove valuable in the long term. At minimum, it is important to determine whether the short term effects are maintained into adulthood. The period from high school to the mid twenties is also an important target for study in its own right, with relatively little longitudinal data available on smoking during this period of rapid social development. This study seeks to follow 7,000 students originally participating in seventh grade prevention researches through the age of 25. Three cohorts have participated in three earlier studies since 1979. Seventy percent of the original cohorts are still in their original school districts and are still the subject of ongoing study. We plan to locate the thirty percent who have left their original schools as well as those still active to obtain locator data to permit annual tracking through 1993. Telephone and in person interviews will be used to monitor smoking and environmental and psychosocial variables related to smoking. The new data will be linked to the existing four year data base for longitudinal evaluation of the earlier prevention programs. In addition the data will provide important new information on the factors which influence smoking from high school graduation through young adulthood.